usr.sbin/ypserv/yp_main.c

   1 /*
   2  * Copyright (c) 1995
   3  *      Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by Bill Paul.
  16  * 4. Neither the name of the author nor the names of any co-contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  * $FreeBSD: src/usr.sbin/ypserv/yp_main.c,v 1.29 2008/02/03 17:39:37 matteo Exp $
  33  * $DragonFly: src/usr.sbin/ypserv/yp_main.c,v 1.5 2005/11/24 22:23:02 swildner Exp $
  34  */
  35
  36 /*
  37  * ypserv startup function.
  38  * We need out own main() since we have to do some additional work
  39  * that rpcgen won't do for us. Most of this file was generated using
  40  * rpcgen.new, and later modified.
  41  */
  42
  43 #include "yp.h"
  44 #include <err.h>
  45 #include <errno.h>
  46 #include <memory.h>
  47 #include <stdio.h>
  48 #include <signal.h>
  49 #include <stdlib.h> /* getenv, exit */
  50 #include <string.h> /* strcmp */
  51 #include <syslog.h>
  52 #include <unistd.h>
  53 #include <rpc/pmap_clnt.h> /* for pmap_unset */
  54 #ifdef __cplusplus
  55 #include <sysent.h> /* getdtablesize, open */
  56 #endif /* __cplusplus */
  57 #include <sys/socket.h>
  58 #include <netinet/in.h>
  59 #include <sys/wait.h>
  60 #include "yp_extern.h"
  61 #include <rpc/rpc.h>
  62
  63 #ifndef SIG_PF
  64 #define SIG_PF void(*)(int)
  65 #endif
  66
  67 #define _RPCSVC_CLOSEDOWN 120
  68 int _rpcpmstart;                /* Started by a port monitor ? */
  69 static int _rpcfdtype;
  70                  /* Whether Stream or Datagram ? */
  71         /* States a server can be in wrt request */
  72
  73 #define _IDLE 0
  74 #define _SERVED 1
  75 #define _SERVING 2
  76
  77 extern void ypprog_1(struct svc_req *, SVCXPRT *);
  78 extern void ypprog_2(struct svc_req *, SVCXPRT *);
  79 extern int _rpc_dtablesize(void);
  80 extern int _rpcsvcstate;         /* Set when a request is serviced */
  81 char *progname = "ypserv";
  82 const char *yp_dir = _PATH_YP;
  83 /*int debug = 0;*/
  84 int do_dns = 0;
  85 int resfd;
  86
  87 struct socktype {
  88         const char *st_name;
  89         int        st_type;
  90 };
  91 static struct socktype stlist[] = {
  92         { "tcp", SOCK_STREAM },
  93         { "udp", SOCK_DGRAM },
  94         { NULL, 0 }
  95 };
  96
  97 static void
  98 _msgout(char *msg)
  99 {
 100         if (debug) {
 101                 if (_rpcpmstart)
 102                         syslog(LOG_ERR, "%s", msg);
 103                 else
 104                         warnx("%s", msg);
 105         } else
 106                 syslog(LOG_ERR, "%s", msg);
 107 }
 108
 109 pid_t   yp_pid;
 110
 111 static void
 112 yp_svc_run(void)
 113 {
 114 #ifdef FD_SETSIZE
 115         fd_set readfds;
 116 #else
 117         int readfds;
 118 #endif /* def FD_SETSIZE */
 119         int fd_setsize = _rpc_dtablesize();
 120         struct timeval timeout;
 121
 122         /* Establish the identity of the parent ypserv process. */
 123         yp_pid = getpid();
 124
 125         for (;;) {
 126 #ifdef FD_SETSIZE
 127                 readfds = svc_fdset;
 128 #else
 129                 readfds = svc_fds;
 130 #endif /* def FD_SETSIZE */
 131
 132                 FD_SET(resfd, &readfds);
 133
 134                 timeout.tv_sec = RESOLVER_TIMEOUT;
 135                 timeout.tv_usec = 0;
 136                 switch (select(fd_setsize, &readfds, NULL, NULL,
 137                                &timeout)) {
 138                 case -1:
 139                         if (errno == EINTR) {
 140                                 continue;
 141                         }
 142                         warn("svc_run: - select failed");
 143                         return;
 144                 case 0:
 145                         if (getpid() == yp_pid)
 146                                 yp_prune_dnsq();
 147                         break;
 148                 default:
 149                         if (getpid() == yp_pid) {
 150                                 if (FD_ISSET(resfd, &readfds)) {
 151                                         yp_run_dnsq();
 152                                         FD_CLR(resfd, &readfds);
 153                                 }
 154                                 svc_getreqset(&readfds);
 155                         }
 156                 }
 157                 if (yp_pid != getpid())
 158                         _exit(0);
 159         }
 160 }
 161
 162 static void
 163 unregister(void)
 164 {
 165         pmap_unset(YPPROG, YPVERS);
 166         pmap_unset(YPPROG, YPOLDVERS);
 167 }
 168
 169 static void
 170 reaper(int sig)
 171 {
 172         int status;
 173         int saved_errno;
 174
 175         saved_errno = errno;
 176
 177         if (sig == SIGHUP) {
 178                 load_securenets();
 179 #ifdef DB_CACHE
 180                 yp_flush_all();
 181 #endif
 182                 errno = saved_errno;
 183                 return;
 184         }
 185
 186         if (sig == SIGCHLD) {
 187                 while (wait3(&status, WNOHANG, NULL) > 0)
 188                         children--;
 189         } else {
 190                 unregister();
 191                 exit(0);
 192         }
 193         errno = saved_errno;
 194         return;
 195 }
 196
 197 static void
 198 usage(void)
 199 {
 200         fprintf(stderr, "usage: ypserv [-h] [-d] [-n] [-p path] [-P port]\n");
 201         exit(1);
 202 }
 203
 204 static void
 205 closedown(int sig)
 206 {
 207         if (_rpcsvcstate == _IDLE) {
 208                 extern fd_set svc_fdset;
 209                 static int size;
 210                 int i, openfd;
 211
 212                 if (_rpcfdtype == SOCK_DGRAM) {
 213                         unregister();
 214                         exit(0);
 215                 }
 216                 if (size == 0) {
 217                         size = getdtablesize();
 218                 }
 219                 for (i = 0, openfd = 0; i < size && openfd < 2; i++)
 220                         if (FD_ISSET(i, &svc_fdset))
 221                                 openfd++;
 222                 if (openfd <= 1) {
 223                         unregister();
 224                         exit(0);
 225                 }
 226         }
 227         if (_rpcsvcstate == _SERVED)
 228                 _rpcsvcstate = _IDLE;
 229
 230         signal(SIGALRM, (SIG_PF)closedown);
 231         alarm(_RPCSVC_CLOSEDOWN / 2);
 232 }
 233
 234 int
 235 main(int argc, char **argv)
 236 {
 237         SVCXPRT *transp = NULL;
 238         int sock;
 239         int proto = 0;
 240         struct sockaddr_in saddr;
 241         socklen_t asize = sizeof (saddr);
 242         int ch;
 243         in_port_t yp_port = 0;
 244         char *errstr;
 245         struct socktype *st;
 246
 247         while ((ch = getopt(argc, argv, "hdnp:P:")) != -1) {
 248                 switch (ch) {
 249                 case 'd':
 250                         debug = ypdb_debug = 1;
 251                         break;
 252                 case 'n':
 253                         do_dns = 1;
 254                         break;
 255                 case 'p':
 256                         yp_dir = optarg;
 257                         break;
 258                 case 'P':
 259                         yp_port = (in_port_t)strtonum(optarg, 1, 65535,
 260                             (const char **)&errstr);
 261                         if (yp_port == 0 && errstr != NULL) {
 262                                 _msgout("invalid port number provided");
 263                                 exit(1);
 264                         }
 265                         break;
 266                 case 'h':
 267                 default:
 268                         usage();
 269                 }
 270         }
 271
 272         load_securenets();
 273         yp_init_resolver();
 274 #ifdef DB_CACHE
 275         yp_init_dbs();
 276 #endif
 277         if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
 278                 int ssize = sizeof (int);
 279
 280                 if (saddr.sin_family != AF_INET)
 281                         exit(1);
 282                 if (getsockopt(0, SOL_SOCKET, SO_TYPE,
 283                                 (char *)&_rpcfdtype, &ssize) == -1)
 284                         exit(1);
 285                 sock = 0;
 286                 _rpcpmstart = 1;
 287                 proto = 0;
 288                 openlog("ypserv", LOG_PID, LOG_DAEMON);
 289         } else {
 290                 if (!debug) {
 291                         if (daemon(0,0)) {
 292                                 err(1,"cannot fork");
 293                         }
 294                         openlog("ypserv", LOG_PID, LOG_DAEMON);
 295                 }
 296                 sock = RPC_ANYSOCK;
 297                 pmap_unset(YPPROG, YPVERS);
 298                 pmap_unset(YPPROG, 1);
 299         }
 300
 301         /*
 302          * Initialize TCP/UDP sockets.
 303          */
 304         memset((char *)&saddr, 0, sizeof(saddr));
 305         saddr.sin_family = AF_INET;
 306         saddr.sin_addr.s_addr = htonl(INADDR_ANY);
 307         saddr.sin_port = htons(yp_port);
 308         for (st = stlist; st->st_name != NULL; st++) {
 309                 /* Do not bind the socket if the user didn't specify a port */
 310                 if (yp_port == 0)
 311                         break;
 312
 313                 sock = socket(AF_INET, st->st_type, 0);
 314                 if (sock == -1) {
 315                         if ((asprintf(&errstr, "cannot create a %s socket",
 316                             st->st_name)) == -1)
 317                                 err(1, "unexpected failure in asprintf()");
 318                         _msgout(errstr);
 319                         free((void *)errstr);
 320                         exit(1);
 321                 }
 322                 if (bind(sock, (struct sockaddr *) &saddr, sizeof(saddr))
 323                     == -1) {
 324                         if ((asprintf(&errstr, "cannot bind %s socket",
 325                             st->st_name)) == -1)
 326                                 err(1, "unexpected failure in asprintf()");
 327                         _msgout(errstr);
 328                         free((void *)errstr);
 329                         exit(1);
 330                 }
 331                 errstr = NULL;
 332         }
 333
 334         if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
 335                 transp = svcudp_create(sock);
 336                 if (transp == NULL) {
 337                         _msgout("cannot create udp service");
 338                         exit(1);
 339                 }
 340                 if (!_rpcpmstart)
 341                         proto = IPPROTO_UDP;
 342                 if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
 343                         _msgout("unable to register (YPPROG, YPOLDVERS, udp)");
 344                         exit(1);
 345                 }
 346                 if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
 347                         _msgout("unable to register (YPPROG, YPVERS, udp)");
 348                         exit(1);
 349                 }
 350         }
 351
 352         if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
 353                 transp = svctcp_create(sock, 0, 0);
 354                 if (transp == NULL) {
 355                         _msgout("cannot create tcp service");
 356                         exit(1);
 357                 }
 358                 if (!_rpcpmstart)
 359                         proto = IPPROTO_TCP;
 360                 if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
 361                         _msgout("unable to register (YPPROG, YPOLDVERS, tcp)");
 362                         exit(1);
 363                 }
 364                 if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
 365                         _msgout("unable to register (YPPROG, YPVERS, tcp)");
 366                         exit(1);
 367                 }
 368         }
 369
 370         if (transp == NULL) {
 371                 _msgout("could not create a handle");
 372                 exit(1);
 373         }
 374         if (_rpcpmstart) {
 375                 signal(SIGALRM, (SIG_PF)closedown);
 376                 alarm(_RPCSVC_CLOSEDOWN / 2);
 377         }
 378 /*
 379  * Make sure SIGPIPE doesn't blow us away while servicing TCP
 380  * connections.
 381  */
 382         signal(SIGPIPE, SIG_IGN);
 383         signal(SIGCHLD, (SIG_PF) reaper);
 384         signal(SIGTERM, (SIG_PF) reaper);
 385         signal(SIGINT, (SIG_PF) reaper);
 386         signal(SIGHUP, (SIG_PF) reaper);
 387         yp_svc_run();
 388         _msgout("svc_run returned");
 389         exit(1);
 390         /* NOTREACHED */
 391 }